Unexpected delays caused long lines in California and Texas as voters waited to cast their ballot in the Super Tuesday primaries.

In the most egregious example, some voters at Texas Southern University had to wait up to seven hours to vote.

The wait times were largely caused by a series of glitches, as well as unexpected voter turnout.

In Harris County, which includes Houston, voting machines were divided equally between Democratic and Republican voters. GOP state leaders had aggressively closed polling locations many of which where in heavily Democratic areas. However, many more Democrats turned out to vote on Tuesday as the Republican primary was canceled.

A Harris County clerk official told The New York Times that TSU was serving as a polling place for the first time in a presidential primary, and that its Election Day turnout exceeded the total turnout from 11 days of early voting.

The site had 10 voting machines designated for each party, and eventually added 14 additional machines for Democratic voters, the clerk said. Of those who voted Tuesday, 1,132 voted in the Democratic primary. Only 68 voted for Republican candidates.

Voting delays were exacerbated by Harris County’s old voting machines, which the county plans to replace by 2021.

There were several long lines in California as well, particularly in Los Angeles, because of its new $300 million voting system glitching.

Some delays in both California and Texas could also be attributed to a switch to countywide voting centers that allow people vote regardless of their residential address. While the centers were intended to make voting more convenient, areas with higher demand became congested.