Susan Walsh, Associated Press
President Barack Obama speaks at a Democratic National Committee reception in San Jose, Calif., Thursday, May 8, 2014. Political committees and groups offered clues to their influence as campaign finance filings dribbled out Tuesday and nomination fights morphed into an all-out battle for control of the Senate.

WASHINGTON — Political committees and groups offered clues to their influence as campaign finance filings dribbled out Tuesday and nomination fights morphed into an all-out battle for control of the Senate.

Deep-pocketed donors helped the parties' campaign committees build a cash reserve that was expected to easily top $100 million by the time the final Federal Election Commission reports were filed by the end of the day. Separately, their allies were sitting on tens of millions more that were ready to be used for negative television ads, mail and phone calls.

Those millions of dollars — and the tactics they fund — already had inundated voters who were picking nominees on Tuesday in Kentucky, Georgia and elsewhere. Heavy spending was already set to follow in next month's primaries in Iowa, Mississippi and Colorado and continue all the way through Election Day on Nov. 4.

The incomplete snapshot of money's power in political races came into focus as parties and outside groups faced Tuesday's deadline to report how much cash they collected in April. Missing from the picture: groups that only report in three-month increments and groups — such as the Koch brothers-backed Americans for Prosperity or the Karl Rove-endorsed Crossroads GPS — that do not have to disclose their finances because, under campaign finance rules, they are considered nonpartisan and nonprofit.

And the reports didn't capture millions spent in Kentucky since May 1 on the hard-fought primary between Senate Republican leader Mitch McConnell and his tea party primary challenger Matt Bevin. Nor did they capture more than $500,000 in recent spending to help Republican state lawmaker Chris McDaniel, who is challenging GOP Sen. Thad Cochran's bid for a seventh term representing Mississippi.

Even so, the finance landscape gave both Democrats and Republicans reasons to be optimistic heading toward November's elections.

Voters, already weary of political ads, are unlikely to get a break.

Democrats' party-controlled committees reported they had raised $285 million so far this cycle and had more than $76 million banked as of May 1.

The Democratic National Committee reported $8.9 million raised in April and reduced its debt to $8.7 million — a new low this election cycle, down from a high of almost $23 million. The DNC said most of that debt is owed to political vendors, such as advertisers, contractors and consultants.

The DNC had $7.9 million in the bank.

The Democrats' Senate campaign arm reported raising $6.3 million in April and had $25 million in hand.

And the Democratic Congressional Campaign Committee reported it raised $7.1 million in April and banked a staggering $43.4 million. For yet another month, the DCCC posted the largest cash-on-hand number so far among committees and outpaced most super PACs as well.

Outside the party's official control, the Democratic-backing House Majority PAC also reported $6.2 million on hand after spending $1.1 million in April. The group, however, pulled in just $343,000 last month. Of that, $250,000 came from George Marcus, a Palo Alto, California, real estate developer.

But Republicans were set to counter that with aggressive spending plans — much of it outside the reporting requirements of campaign-finance laws.

Americans for Prosperity, the group backed by billionaire brothers Charles and David Koch, was set to spend $125 million to help Republicans in Senate races. All of it was likely to be outside campaign finance reports.

And Rove's political machine signaled it was ready to spend almost $15 million on ads in four states with competitive Senate races. But of that sum, about half is for races in Arkansas and Alaska and is funneled through American Crossroads, a super PAC that discloses its donors. The other half was through the nonprofit Crossroads GPS, which booked TV time in North Carolina, Colorado, Arkansas and Alaska.

Inside the GOP's official committees, the National Republican Senatorial Committee raised $6 million in April and ended the month with $21.9 million on hand. The Democratic Senatorial Campaign Committee has outraised the Republican rival 14 of the last 16 months.

House Republicans' campaign arm and the Republican National Committee were set to release their fundraising tallies later Tuesday.

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