At The Washington Post, Brian Arbour uses the 1988 election as a point of departure for discussing partisan voting in congressional elections. Even though the Dukakis-Bentsen lost Texas, Bentsen won reelection to the Senate by a wide margin, running 16 points ahead of the ticket. In 2014, by contrast, no Democratic Senate candidate in a key race ran more than five points ahead of Obama’s 2012 total.
Bentsen’s experience was not unusual. That year, 16 other Senators won election in a state their party’s presidential nominee did not carry (15 Democrats won in Bush states; two Republicans won in Dukakis states). The same was true in the U.S. House. Democrats won a majority for the 18th straight election, winning the popular vote 53 to 46 percent — the reverse of the presidential popular vote, when Bush defeated Michael Dukakis 53 to 46 percent.
In 2014, Election Day was a bad day for Democrats in red or purple states precisely because they didn’t do what Bentsen and other Democrats did in 1988. Democrats today had very little of what political scientists call the “personal vote” — the portion of a candidate’s support that derives from his or her personal qualities and qualifications. Many fewer voters were willing to go against their presidential party preferences in 2014 than they were in 1988.
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As they have for several elections now, national factors such as partisanship and presidential approval largely drove the results of the 2014 election. According to the exit poll, 92 percent of Democrats and 94 percent of Republicans voted for their party’s House candidate. As voters have sorted themselves more clearly as Republicans and Democrats, they have become more likely to support candidates of the same party in different elections and have become less likely to be swayed by personal factors such as a candidate’s personality or political record.