CHICAGO (Reuters) - The wave of voter discontent that put Democrats in charge of the U.S. House of Representatives also hit state legislatures, where the party won control of more chambers than Republicans.

Democrats picked up control of at least nine chambers in Tuesday's election, winning the House and Senate in Iowa and New Hampshire, the House in Michigan, Minnesota, Oregon, and Indiana, and the Wisconsin Senate, according to the National Conference of State Legislatures.

"The Democrats have won pretty much across the board," said Tim Storey, an elections analyst at the nonpartisan group.

He said the outcomes of House races in Maine, Montana, Oregon and Pennsylvania were still up in the air. Republicans, meanwhile, managed to tie the Oklahoma Senate, which had been controlled by Democrats.

So far, Democrats control both chambers in 21 states, while Republicans control 15 and 9 were split between the two parties, according to Storey.

Heading into the election, in which 6,181 out of 7,382 legislative seats were on ballots, 20 legislatures were controlled by Republicans, 19 by Democrats and 10 were split between the two parties. In terms of overall legislative seats, Democrats had 18 more than Republicans.

Nebraska's single-chamber legislature is nonpartisan.

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