(CNN) The primaries in Illinois on Tuesday night were, for the most part melodramatic -- some big names got scares but there were no major upsets.

There was, however, some good news for Democrats: In the second of two statewide primaries this year ( Texas being the other ), turnout was significantly higher for Democrats than in either 2010 or 2014.

There were just under 1.3 million votes cast in the Illinois Democratic primary Tuesday to just over 700,000 in the Republican primary. Put another way, 64% of the votes cast were on the Democratic line, compared with only 36% on the Republican line. Now, Illinois is a blue state, but even taking that into account, it was an impressive performance for Democrats.

Dating back to 1998 , there has never been a midterm year in which there was a higher percentage of two-party votes cast in the Illinois Democratic primary compared with 2018. Importantly, this includes 2010, when both the Democrats and Republicans had competitive gubernatorial primaries, like this year. In 2010, just 54% of all primary votes were cast in the Democratic primary when Republicans gained over 60 seats across the country and control of the US House.

Now, as with Texas, it's the case that there isn't a clear connection with the primary vote in Illinois and the eventual result in November. Democrat Pat Quinn actually won the general election for governor of Illinois in 2010, for example. Democrats also had their previous highest turnout in 2002 (58% of the two-party vote, compared with 64% in 2018), and Republicans did well in that year's midterm election nationally.

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