The larger Capitol grounds aren't free from restrictions either; senators can't solicit for donations anywhere in the Capitol's roughly 290 acres.
2. Don't use the trappings of your office to help your campaign.
Prohibited resources include but are not limited to: Senate equipment, buildings, and the time of your Hill staffers. But there are two exceptions to that last rule: Senate and campaign schedulers are allowed to coordinate with each other; and Senate press secretaries can respond to "occasional" or "incidental" campaign-related questions. They just can't give campaign-only interviews from inside their Hill offices.
3. Don't use any TV clips from your last floor speech in a campaign ad—no matter how rousing they may be.
In the words of the Senate Manual: "The use of any tape duplication of radio or television coverage of the proceedings of the Senate for political campaign purposes is strictly prohibited."
4. Senate staffers can't work for your campaign on the taxpayers' dime.
This doesn't mean they can't work for the campaign at all; it just means they have to do so on their own time—through volunteer work or as paid campaign employees. (And they definitely can't use Senate resources or space for campaign work.) If staffers, for example, choose to reduce their hours in the Senate in order to volunteer or officially work for a campaign, they have that flexibility, from the Ethics Committee's perspective. But they need to do at least one day's worth of work in the Hill office per week to retain their Senate employment, their Senate pay must be adjusted based on how many hours they spend on official business, and their Senate pay can't be inflated to compensate for their extracurricular work on a campaign.
5. Staffers can't contribute money, either.
It's a violation of federal law for Senate staffers to donate to their own boss's campaign. Contributing time as a volunteer or employee isn't considered a contribution.
6. Your campaign office can't be given any special privileges that outside organizations don't get.
A Senate Ethics Committee cheat sheet uses document requests as an example here: Senate staff can't turn over, say, a copy of a member's floor speech to his or her campaign staff if they wouldn't honor a similar request from another outside group or person, "without regard to political affiliation."
7. Don't link to your campaign website from your official Hill website—or vice versa.
Sorry, but those earnest voters examining the policy section of your website can't be directed to check out your campaign site. They just can't.
8. Beware campaign donations that inadvertently come through your office.
There are only three people employed in a senator's office, known as political fund designees, who are allowed to ask for and take in campaign donations—but not while using Senate resources, and "only for the Senator's principal campaign committee, a political campaign committee controlled by a Senator or group of Senators, or a state or local committee of a national party." If an unsolicited contribution is mailed or delivered in person to a senator's Hill office, it's got to be sent to the campaign within seven days by a political fund designee.