It’s still too early to know exactly how competitive many of the challengers can be. At this point, there is a big difference in the competitiveness of the races from the top three to bottom three on this list. And as the most recent fundraising reports to the Federal Election Commission illustrated, nearly all of the incumbents’ opponents are starting out in deep financial holes.
Still, with outside groups such as the Club for Growth and the Senate Conservatives Fund beginning to engage, a challenger’s money isn’t the only threat — and any of these races could theoretically take off.
Here are the seven Republican senators most vulnerable to a primary challenge, in order:
3. Thad Cochran, Mississippi
This name could leap off the list by the end of this year, as Cochran hasn’t even announced whether he’ll seek re-election. His third-quarter report offered no evidence that he intends to run again, as he raised just $53,000. But the veteran appropriator would likely have no trouble turning on the fundraising engine. Still, outside groups last week quickly endorsed the candidacy of his primary opponent, state Sen. Chris McDaniel. And the Club for Growth is already on TV introducing McDaniel to the state.