Sen. Marco Rubio speaks as he announces his candidacy for the Republican presidential nomination during an event at the Freedom Tower on April 13, 2015 in Miami, Florida.National Journal

Q: Which Republican presidential candidate should Democrats fear most?

Sen. Marco Rubio speaks as he announces his candidacy for the Republican presidential nomination during an event at the Freedom Tower on April 13, 2015 in Miami, Florida. (Joe Raedle/Getty Images)DEMOCRATS (48 votes)

Jeb Bush: 37%Marco Rubio: 29%Scott Walker: 5%John Kasich: 13%Rand Paul: 4%Mike Huckabee: 2%Ben Carson: 0%Chris Christie: 0%Ted Cruz: 0%Carly Fiorina: 0%

Jeb Bush

"He's the one who can unify his party at the end of the day and win swing voters in November 2016."

"If he can get through the primaries, he has the most crossover appeal to moderates and undecideds. He would also make great inroads with Hispanic voters."

"He'll have the deep-pocket Republican establishment behind him. Rubio a close second."

Marco Rubio

"He's young, handsome, has charisma. Thank God he is not nearly as good a candidate as Obama was."

"Rubio is likable, dynamic, and has a great story to tell, and he tells it well. He can connect. His earnest, youthful contrast to [Hillary Clinton] is worrisome."

"Broadest appeal and most different from Hillary. Represents [the] fresh"Š/"Šnew."

Scott Walker

"Probably the best politician in the group. Also the least likely to be a good president if he wins."

"Danger is Scott Walker could bore the electorate to victory."

Q: Which Republican presidential candidate should Democrats fear most?

REPUBLICANS (56 VOTES)

Marco Rubio: 43%Jeb Bush: 21%John Kasich: 12%Scott Walker: 9%Chris Christie: 7%Ben Carson: 2%Ted Cruz: 2%Carly Fiorina: 2%Rand Paul: 2%Mike Huckabee: 0%

 Marco Rubio

"He represents a significant turning of the page for the GOP and has the potential to appeal to Hispanics and millennials in ways the others can't."

"A powerful combination of personal story and great ability to inspire. It's up to his campaign to see how far he can go."

"He is a natural campaigner that will fare well with the independents."

Jeb Bush

"Will keep GOP base, while getting more Latino votes than his brother."

"Jeb can better battle Hillary for the center and exploit her pandering to the Warren faction."

John Kasich

"Experienced, centered, Ohio, with little baggage. Perfect matchup with Clinton."

Scott Walker

"Midwest governor who turned blue state red, beat public-sector unions three times at polls, and made Wisconsin a right-to-work state. That's a tough hombre."

Chris Christie

"If he runs and survives the primary, his tell-it-like-it-is persona will be perfected, and he rivals Bill Clinton in terms of charisma. Hillary can't compete."

. . . . . . . . . . . . . . . . . .

Democratic Political Insiders  Jill Alper, John Anzalone, Brad Bannon, Dave Beattie, Andy Bechhoefer, Cornell Belcher, Matt Bennett, Mitchell W. Berger, Mike Berman, Stephanie Bosh, Paul Brathwaite, Donna Brazile, Mark Brewer, Ed Bruley, George Bruno, Bonnie Campbell, Bill Carrick, Guy Cecil, Martin J. Chávez, Tony Coelho, Larry Cohen, Jerry Crawford, Brendan Daly, Jeff Danielson, Peter Daou, Howard Dean, Scott DeFife, Jim Demers, Tad Devine, David Di Martino, Debbie Dingell, Monica Dixon, Patrick Dorton, Pat Dujakovich, Anita Dunn, Jeff Eller, Steve Elmendorf, Carter Eskew, Vic Fazio, Peter Fenn, Scott Ferson, Jim Fleischmann, Tina Flournoy, Don Foley, Jeffrey Forbes, Vincent Frillici, Gina Glantz, Niles Godes, John Michael Gonzalez, Joe Grandmaison, Anna Greenberg, Stan Greenberg, Pat Griffin, Larry Grisolano, Michael Gronstal, Lisa Grove, Marcia Hale, Jill Hanauer, Dick Harpootlian, Paul Harstad, Laura Hartigan, Doug Hattaway, Mike Henry, Karen Hicks, Leo Hindery Jr., Harold Ickes, Marcus Jadotte, John Jameson, Steve Jarding, Jonathon Jones, Jim Jordan, Gale Kaufman, Lisa Kountoupes, Celinda Lake, David Lang, Penny Lee, Chris Lehane, Jeff Link, Bob Maloney, Jim Manley, Steve Marchand, Jim Margolis, Paul Maslin, Keith Mason, Susan McCue, Gerald McEntee, Steve McMahon, Tom McMahon, Phil McNamara, David Medina, Michael Meehan, Mark Mellman, John Merrigan, Michael Monroe, Steve Murphy, Janet Napolitano, David Nassar, Marcia Nichols, John Norris, Tom Ochs, Tom O'Donnell, Jeffrey Peck, Debora Pignatelli, Tony Podesta, Jefrey Pollock, Jack Quinn, Larry Rasky, Mame Reiley, Ed Rendell, Steve Ricchetti, Will Robinson, Steve Rosenthal, David Rudd, Ryan Rudominer, John Ryan, Michael Sargeant, Stephanie Schriock, Terry Shumaker, Sean Sinclair, Phil Singer, Erik Smith, Doug Sosnik, Greg Speed, Darry Sragow, Ken Strasma, Doug Thornell, Jeffrey Trammell, Ed Turlington, Rick Wiener, James Williams, JoDee Winterhof, Brian Wolff, Jon Youngdahl, and Jim Zogby.

GOP Political Insiders  Dan Allen, Stan Anderson, Gary Andres, Saulius (Saul) Anuzis, Rich Ashooh, Whit Ayres, Brett Bader, Mitch Bainwol, Brian Baker, Gary Bauer, David Beckwith, Paul Bennecke, Clark Benson, Wayne Berman, Brian Bieron, Charlie Black, Kirk Blalock, Carmine Boal, Jeff Boeyink, Ron Bonjean, Jeff Buley, Luke Byars, Nick Calio, Al Cardenas, Danny Carroll, Alex Castellanos, Ron Christie, Jim Cicconi, Jonathan Collegio, Rob Collins, Cesar Conda, Jake Corman, Scott Cottington, Jay Cranford, Greg Crist, Diane Crookham-Johnson, Fergus Cullen, Tom Davis, Mike Dennehy, Ken Duberstein, Debi Durham, Sara Fagen, Frank Fahrenkopf, John Feehery, Don Fierce, Mindy Finn, Carl Forti, Alex Gage, Bruce A. Gates, Sam Geduldig, Adam Geller, Benjamin Ginsberg, David Girard-diCarlo, Bill Greener, Jonathan Grella, Lanny Griffith, Janet Mullins Grissom, Doug Gross, Todd Harris, Steve Hart, Christopher Healy, Ralph Hellmann, Chris Henick, Terry Holt, David Iannelli, Ed Ingle, Jim Innocenzi, Clark Judge, David Keating, David Kensinger, Bob Kjellander, Ed Kutler, Chris LaCivita, Jim Lake, Steven Law, Steve Lombardo, Kevin Madden, Joel Maiola, Gary Maloney, David Marin, Mary Matalin, Dan Mattoon, Brian McCormack, Mark McKinnon, Kyle McSlarrow, Ken Mehlman, Jim Merrill, Lisa Camooso Miller, Tim Morrison, Mike Murphy, Phil Musser, Ron Nehring, Terry Nelson, Neil Newhouse, David Norcross, Ziad Ojakli, Jack Oliver, Todd Olsen, Kevin O'Neill, Connie Partoyan, Billy Piper, Van B. Poole, Tom Rath, Scott Reed, David Rehr, Tom Reynolds, Steve Roberts, Jason Roe, David Roederer, Dan Schnur, Russ Schriefer, Rich Schwarm, Brent Seaborn, Rick Shelby, Andrew Shore, Kevin Shuvalov, Don Sipple, Ken Spain, Fred Steeper, Bob Stevenson, Terry Sullivan, David Tamasi, Eric Tanenblatt, Richard Temple, Heath Thompson, Jay Timmons, Warren Tompkins, Ted Van Der Meid, Dirk Van Dongen, Jan van Lohuizen, Stewart Verdery, Dick Wadhams, John Weaver, Lezlee Westine, Dave Winston, Ginny Wolfe, Fred Wszolek, and Matthew Zablud.

Q: Which Republican presidential candidate should Democrats fear most?

Sen. Marco Rubio speaks as he announces his candidacy for the Republican presidential nomination during an event at the Freedom Tower on April 13, 2015 in Miami, Florida. (Joe Raedle/Getty Images)DEMOCRATS (48 votes)

Jeb Bush: 37%Marco Rubio: 29%Scott Walker: 5%John Kasich: 13%Rand Paul: 4%Mike Huckabee: 2%Ben Carson: 0%Chris Christie: 0%Ted Cruz: 0%Carly Fiorina: 0%

Jeb Bush

"He's the one who can unify his party at the end of the day and win swing voters in November 2016."

"If he can get through the primaries, he has the most crossover appeal to moderates and undecideds. He would also make great inroads with Hispanic voters."

"He'll have the deep-pocket Republican establishment behind him. Rubio a close second."

Marco Rubio

"He's young, handsome, has charisma. Thank God he is not nearly as good a candidate as Obama was."

"Rubio is likable, dynamic, and has a great story to tell, and he tells it well. He can connect. His earnest, youthful contrast to [Hillary Clinton] is worrisome."

"Broadest appeal and most different from Hillary. Represents [the] fresh"Š/"Šnew."

Scott Walker

"Probably the best politician in the group. Also the least likely to be a good president if he wins."

"Danger is Scott Walker could bore the electorate to victory."

Q: Which Republican presidential candidate should Democrats fear most?

REPUBLICANS (56 VOTES)

Marco Rubio: 43%Jeb Bush: 21%John Kasich: 12%Scott Walker: 9%Chris Christie: 7%Ben Carson: 2%Ted Cruz: 2%Carly Fiorina: 2%Rand Paul: 2%Mike Huckabee: 0%

 Marco Rubio

"He represents a significant turning of the page for the GOP and has the potential to appeal to Hispanics and millennials in ways the others can't."

"A powerful combination of personal story and great ability to inspire. It's up to his campaign to see how far he can go."

"He is a natural campaigner that will fare well with the independents."

Jeb Bush

"Will keep GOP base, while getting more Latino votes than his brother."

"Jeb can better battle Hillary for the center and exploit her pandering to the Warren faction."

John Kasich

"Experienced, centered, Ohio, with little baggage. Perfect matchup with Clinton."

Scott Walker

"Midwest governor who turned blue state red, beat public-sector unions three times at polls, and made Wisconsin a right-to-work state. That's a tough hombre."

Chris Christie

"If he runs and survives the primary, his tell-it-like-it-is persona will be perfected, and he rivals Bill Clinton in terms of charisma. Hillary can't compete."

. . . . . . . . . . . . . . . . . .

Democratic Political Insiders  Jill Alper, John Anzalone, Brad Bannon, Dave Beattie, Andy Bechhoefer, Cornell Belcher, Matt Bennett, Mitchell W. Berger, Mike Berman, Stephanie Bosh, Paul Brathwaite, Donna Brazile, Mark Brewer, Ed Bruley, George Bruno, Bonnie Campbell, Bill Carrick, Guy Cecil, Martin J. Chávez, Tony Coelho, Larry Cohen, Jerry Crawford, Brendan Daly, Jeff Danielson, Peter Daou, Howard Dean, Scott DeFife, Jim Demers, Tad Devine, David Di Martino, Debbie Dingell, Monica Dixon, Patrick Dorton, Pat Dujakovich, Anita Dunn, Jeff Eller, Steve Elmendorf, Carter Eskew, Vic Fazio, Peter Fenn, Scott Ferson, Jim Fleischmann, Tina Flournoy, Don Foley, Jeffrey Forbes, Vincent Frillici, Gina Glantz, Niles Godes, John Michael Gonzalez, Joe Grandmaison, Anna Greenberg, Stan Greenberg, Pat Griffin, Larry Grisolano, Michael Gronstal, Lisa Grove, Marcia Hale, Jill Hanauer, Dick Harpootlian, Paul Harstad, Laura Hartigan, Doug Hattaway, Mike Henry, Karen Hicks, Leo Hindery Jr., Harold Ickes, Marcus Jadotte, John Jameson, Steve Jarding, Jonathon Jones, Jim Jordan, Gale Kaufman, Lisa Kountoupes, Celinda Lake, David Lang, Penny Lee, Chris Lehane, Jeff Link, Bob Maloney, Jim Manley, Steve Marchand, Jim Margolis, Paul Maslin, Keith Mason, Susan McCue, Gerald McEntee, Steve McMahon, Tom McMahon, Phil McNamara, David Medina, Michael Meehan, Mark Mellman, John Merrigan, Michael Monroe, Steve Murphy, Janet Napolitano, David Nassar, Marcia Nichols, John Norris, Tom Ochs, Tom O'Donnell, Jeffrey Peck, Debora Pignatelli, Tony Podesta, Jefrey Pollock, Jack Quinn, Larry Rasky, Mame Reiley, Ed Rendell, Steve Ricchetti, Will Robinson, Steve Rosenthal, David Rudd, Ryan Rudominer, John Ryan, Michael Sargeant, Stephanie Schriock, Terry Shumaker, Sean Sinclair, Phil Singer, Erik Smith, Doug Sosnik, Greg Speed, Darry Sragow, Ken Strasma, Doug Thornell, Jeffrey Trammell, Ed Turlington, Rick Wiener, James Williams, JoDee Winterhof, Brian Wolff, Jon Youngdahl, and Jim Zogby.

GOP Political Insiders  Dan Allen, Stan Anderson, Gary Andres, Saulius (Saul) Anuzis, Rich Ashooh, Whit Ayres, Brett Bader, Mitch Bainwol, Brian Baker, Gary Bauer, David Beckwith, Paul Bennecke, Clark Benson, Wayne Berman, Brian Bieron, Charlie Black, Kirk Blalock, Carmine Boal, Jeff Boeyink, Ron Bonjean, Jeff Buley, Luke Byars, Nick Calio, Al Cardenas, Danny Carroll, Alex Castellanos, Ron Christie, Jim Cicconi, Jonathan Collegio, Rob Collins, Cesar Conda, Jake Corman, Scott Cottington, Jay Cranford, Greg Crist, Diane Crookham-Johnson, Fergus Cullen, Tom Davis, Mike Dennehy, Ken Duberstein, Debi Durham, Sara Fagen, Frank Fahrenkopf, John Feehery, Don Fierce, Mindy Finn, Carl Forti, Alex Gage, Bruce A. Gates, Sam Geduldig, Adam Geller, Benjamin Ginsberg, David Girard-diCarlo, Bill Greener, Jonathan Grella, Lanny Griffith, Janet Mullins Grissom, Doug Gross, Todd Harris, Steve Hart, Christopher Healy, Ralph Hellmann, Chris Henick, Terry Holt, David Iannelli, Ed Ingle, Jim Innocenzi, Clark Judge, David Keating, David Kensinger, Bob Kjellander, Ed Kutler, Chris LaCivita, Jim Lake, Steven Law, Steve Lombardo, Kevin Madden, Joel Maiola, Gary Maloney, David Marin, Mary Matalin, Dan Mattoon, Brian McCormack, Mark McKinnon, Kyle McSlarrow, Ken Mehlman, Jim Merrill, Lisa Camooso Miller, Tim Morrison, Mike Murphy, Phil Musser, Ron Nehring, Terry Nelson, Neil Newhouse, David Norcross, Ziad Ojakli, Jack Oliver, Todd Olsen, Kevin O'Neill, Connie Partoyan, Billy Piper, Van B. Poole, Tom Rath, Scott Reed, David Rehr, Tom Reynolds, Steve Roberts, Jason Roe, David Roederer, Dan Schnur, Russ Schriefer, Rich Schwarm, Brent Seaborn, Rick Shelby, Andrew Shore, Kevin Shuvalov, Don Sipple, Ken Spain, Fred Steeper, Bob Stevenson, Terry Sullivan, David Tamasi, Eric Tanenblatt, Richard Temple, Heath Thompson, Jay Timmons, Warren Tompkins, Ted Van Der Meid, Dirk Van Dongen, Jan van Lohuizen, Stewart Verdery, Dick Wadhams, John Weaver, Lezlee Westine, Dave Winston, Ginny Wolfe, Fred Wszolek, and Matthew Zablud.

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