Montana Rep. Denny Rehberg’s decision to run for the Senate, which the Republican will announce on Saturday, opens up a potentially competitive at-large House seat.

Businessman Steve Daines (R) will announce Thursday that he is leaving the Senate race to instead run for Rehberg’s House seat. Daines has been running for office since November and had about $200,000 in cash on hand as of the beginning of the year.

So far he is the only Republican to step forward, while a Democratic state legislator has already announced she is running now that Rehberg is out of the race.

State Rep. Franke Wilmer (D), a political science professor at Montana State University, told Roll Call on Wednesday that she has the experience necessary to both run an effective campaign and serve in Congress.

Former students now working in the field across the country have already called offering to help.

Meanwhile, helping push the buttons and get the campaign off the ground early is Wilmer’s fellow state Rep. Ellie Boldman Hill, who was named among Time magazine’s “40 under 40” rising American political stars in October.

Wilmer met Tuesday with Gov. Brian Schweitzer (D), who offered her advice and encouragement for her bid. Wilmer expects a competitive primary.

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