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Indiana's next major Senate race is arriving two years early, scrambling plans for a collection of ambitious Republicans in a place where many expected the next statewide opportunity to come in 2018, not 2016.

The question facing these Republicans after Sen. Dan Coats's retirement announcement Tuesday: How many of them will redirect their hopes toward next year's open seat, which is already drawing interest from a veritable fleet of GOP leaders, as opposed to waiting and trying to take on first-term Democratic Sen. Joe Donnelly in 2018? Those decisions mean everything now in a state that Democrats now eagerly tout as a new "“ if clearly second-tier "“ pick-up opportunity next year.

In a state with a deep, talented bench of GOP politicians and a lot of pent-up ambition, another opening for higher office might count as a good problem to have. But it's also a recipe for a primary free-for-all in which an array of credible Republicans jump at the chance to win a Senate seat sooner than most expected would be possible. There are few natural reasons why any of the Republicans considering campaigns would be better-suited to 2016 versus 2018.

"I think there were some people who were maybe jockeying for positions in 2018, and are now are reevaluating whether they're ready to go for 2016," said Tim Berry, chairman of the Indiana GOP. "Which race is better? That's the million dollar question that each of these individuals is probably evaluating at this time."

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The list of Republicans considering a campaign includes a quintet of Congress members -- Reps. Jackie Walorski. Marlin Stutzman, Todd Rokita, Susan Brooks, and Todd Young -- plus state House Speaker Brian Bosma and Eric Holcomb, a longtime top aide to former Indiana Gov. Mitch Daniels, ex-chairman of the State Republican Party, and Coats's state-based chief of staff.

According to Coats, Holcomb had been thinking about running against Donnelly in two years. But the political operative reconsidered after Tuesday, announcing that he would take a leave of absence from the senator's office.

His thinking likely reflects that of his potential rivals. The 2018 race guaranteed an open Republican primary and the chance to take on a Democratic incumbent most consider vulnerable. Donnelly won in 2012, a good Democratic year, against the error-prone Richard Mourdock. Some GOP operatives will also relish the chance to prepare for a marquee statewide race for an extra two years.

"There's certainly some ambition there among all of them that may get in the way off an alliance people thought was there, and I think that's the uncertainty at this time," said one Indiana Republican, who requested anonymity to discuss deliberations within the party.

(RELATED: Indiana Republican Sen. Dan Coats Is Retiring)

But a race against Donnelly would still be difficult, in-state political experts say, and a far cry from a 2016 election not featuring an incumbent.

"An open seat is very different from taking on an incumbent," said Andrew Downs, director of The Mike Downs Center for Indiana Politics. "In both cases you're talking about running in a conservative state, but it's a conservative state that has a tendency to like its incumbents."

Other GOP strategists suggested candidates who decide to run in 2016 could do so with an eye on 2018. Those forced to bow out of the race next year, they say, could use the experience to launch a new campaign in the next political cycle.

"You've got some people who assumed that Dan would run again, so they had 2018 on their minds," said Pete Seat, a Republican strategist and Holcomb ally. "It's happened more than once in the state where someone for office, loses in the primary and ends up getting something else down the line. That might be part of a calculation—maybe run in 2016, build up statewide name ID, and then mount a campaign in 2018."

Coats's retirement immediately sparked speculation that Evan Bayh, the popular former Indiana governor and senator, would seek to return to the state and run as the Democratic nominee "“ a decision that would have vaulted Indiana into a first-tier Senate battleground in 2016. Bayh still has nearly $10 million stockpiled in a federal campaign account.

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But Dan Parker, a longtime Bayh adviser, said unequivocally that his former boss wasn't running next year.

"He's already received calls from people urging him to run for U.S. Senate," Parker said. "He just wanted me to share that he is not a candidate for Senate in 2016."

Other Democrats who could potentially seek the seat include former Rep. Baron Hill and Brad Ellsworth, the party's nominee for Senate in 2010. Whether any of them can defeat the eventual nominee will depend in large part on the national environment during next year's presidential race. Anything short of a strong year for Democrats will likely make winning Indiana difficult unless the Republican nominee commits serious errors.

But Democrats point out that Obama won the state in 2008 (though he lost it by 10 points in 2012), followed by Donnelly's victory in 2012. And they argue Hillary Clinton's presence on the top of the ticket could help the party compete better in a culturally conservative area that has expressed deepening antipathy for President Obama over the course of his presidency.

"Indiana's Senate race is now one of the most competitive Senate races in the country, and Democrats are ready to put together a strong campaign just like we did in 2012," said Jon Tester, chairman of the Democratic Senatorial Campaign Committee. "We're confident that we will find a great candidate who will put Indiana first and win this seat in 2016."

Coats is the third senator to announce his retirement this year, after Democratic Sens. Barbara Boxer and Barbara Mikulski, and the first Republican to do so. GOP officials have said they are optimistic the party will avoid the spate of retirements this election cycle that Democrats suffered in 2014, when Sens. Max Baucus, Tim Johnson, Jay Rockefeller, Tom Harkin, and Carl Levin each stepped down. Democrats went on to lose four of those five races, keeping only Michigan in their column.

CORRECTION: A previous version of this story misidentified Lt. Gov. Sue Ellspermann's time in office. She is the current lieutenant governor.


Scott Bland and Kimberly Railey contributed to this article

This article is from the archive of our partner National Journal.

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