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Democrats, Republicans and the outside groups funding massive television blitzes have spent more than $100 million on television time to air general-election ads in battleground states critical to winning control of the Senate, according to public documents filed with television stations nationwide.

The two sides have bought or reserved more than $116 million since the beginning of January, those documents show. Many of the advertisements have already run; others will air closer to Election Day as campaigns and outside groups spend money early to lock in low rates and the best television spots.

The race for a North Carolina seat held by Sen. Kay Hagan (D) has drawn the most attention, those documents show. Since the beginning of the year, Republicans have spent more than $13 million on the contest, while Democrats have dropped $11 million to defend the senator. Hagan will face state House Speaker Thom Tillis (R) in November. Tillis and his allies spent a few million dollars getting him through the May 6 primary, but most of the GOP’s money has gone toward attacking Hagan.

Voters in Alaska have been overrun by advertising as well. Republicans have spent more than $10.8 million attacking Sen. Mark Begich (D) and bolstering their own candidate. The national party establishment favors former state attorney general Dan Sullivan, although Sullivan will have to make it through an August primary against two other contenders. Democrats and Begich’s campaign have bought just over $8.9 million in ads on his behalf.

The two sides have spent a total of more than $15 million on airtime in three other states: Colorado, where Sen. Mark Udall (D) faces a tough challenge from Rep. Cory Gardner (R); Michigan, where Rep. Gary Peters (D) leads recent polls against former secretary of state Terri Lynn Land (R); and Arkansas, where Sen. Mark Pryor (D) will go up against Rep. Tom Cotton (R) in November. In all three of those states, Democrats have spent more money than Republicans.

Overall, the two sides are close to parity in 2014. Republican candidates and outside groups have spent $58.6 million since the beginning of the year, while Democratic candidates and their allies have dropped $57.7 million. Republicans have outspent Democrats by the widest margins in Alaska and North Carolina, by $1.5 million to $2 million in each state, while Democrats have outspent Republicans by the heaviest margin in Louisiana, by more than $3.3 million. Republicans have yet to invest heavily in Louisiana on behalf of their favored candidate, Rep. Bill Cassidy.

The spending figures are not exact and count only money spent on the general-election campaign. For example, in Kentucky, Senate Minority Leader Mitch McConnell (R) spent millions to defeat a conservative challenger in the May 20 primary, but most of that money was spent talking to primary voters. We’ve counted only the money spent since the May 20 primary in the Bluegrass State, where Republicans have spent about $590,000 in the past month and a half compared with about $150,000 for Democratic nominee Alison Lundergan Grimes.