MISSOULA, Mont. -

With mid-term campaigns underway, candidates who aim to be Montana’s elected representatives in the nation’s capital are well down the campaign trail.

There's a lot on the line.  Montana’s senior U.S. Senator, Max Baucus, is vacating a seat he has held for six terms, and the state’s sole representative in the U.S. House is leaving in a bid to replace him.  That means two key races are up for grabs.

With primary elections just 4 months away, NBC Montana went digging through campaign finance reports for a measure of how the top candidates for the state’s U.S. House seat are doing.

We tracked down year-end financial reports from the Federal Election Commission and cross-checked them with political watchdog web site OpenSecrets.org.

Here’s what we found: Of the six candidates who have declared their candidacy, three have raised a total of almost $1.2 million dollars.

At the top of the list, State Senator and Whitefish resident Ryan Zinke. He closed out 2013 having raised over $447,500. 

Zinke’s a retired Navy Seal and he’s getting financial support from committees like Afghanistan and Iraq Veterans for Congress and the Freedom Defense Fund. 

So far, after expenses, Zinke has about $344,000 in his campaign account.

Democrat John Lewis, a former aide to retiring Sen. Baucus, hauled in a reported $394,000 by the end of last year. 

Roughly $33,000 of that comes from individual donors who can't be traced by name, because their donations are reported by ActBlue, a political action committee established in June of 2004.  ActBlue is a major fund-raising tool for Democrats.  The website bundles contributions from individuals and sends them to specific candidates.

Lewis’ committee donations follow the party line with donations from the Democratic Congressional Committee and the American Association for Justice.

The third major player in this batch of reports is Republican Corey Stapleton of Billings.  He’s a former State Senator who cut his teeth on statewide politics in an unsuccessful bid for Governor in 2012.

Stapleton's $330,000 of contributions show his political strength in eastern Montana, though it's by far the lowest of the three top fund-raisers, and he’s spending it.  Stapleton closed the last quarter with just $57,000 in the bank.