U.S. Sen. John McCain's dramatic thumbs-down in July signaled the collapse of Republican health-care plans. It also reflects the trajectory of the Arizona delegation's positions on President Donald Trump's legislative agenda.

The state's GOP members voted less reliably with the administration between July and September than during the first six months of the year, according to an analysis by FiveThirtyEight of roll-call votes on issues where the White House's preference was clear.

Arizona Democrats found some common ground with Trump during the third quarter, but remained overwhelmingly at odds with the president's positions.

Support on roll-call votes is only one measure of how members line up with the administration.

McSally leads

Nine months into the year, U.S. Rep. Martha McSally, R-Ariz., is the state's most reliable vote for Trump's legislative wishes, siding with the administration's position 96 percent of the time.

U.S. Rep. Raúl Grijalva, D-Ariz., is the most-reliable Trump agenda opponent, voting with the White House 9 percent of the time.

For most in the delegation, the few votes taken in the third quarter offered little to like.

McCain, for example, voted to allow the July health-care debate to proceed in the Senate. After that, he opposed Trump's position four straight times. That included the memorable health-care vote, as well as the vote to sanction Russia that Trump opposed.

U.S. Rep. Andy Biggs, R-Ariz., voted against the administration's position in four of the nine House votes where Trump's position was clear. That was the same number as Democratic U.S. Reps. Tom O'Halleran and Kyrsten Sinema.

In Biggs' case, he is typically holding out for more conservative bills, not more centrist ones.

Declining support

Support for Trump's positions among Arizona's delegation has fallen each quarter so far.

From January through March, McCain and U.S. Sen. Jeff Flake, R-Ariz., voted with Trump for 63 of the 64 votes that mattered. In the second quarter, the senators voted with Trump 14 of 19 times. In the third quarter, they backed Trump on five of 11 votes.

A similar trend has played out in the U.S. House.

Arizona's Republican members backed Trump on 99 percent of the votes in the first quarter. In the second quarter, it fell to 90 percent. In the third quarter, it dropped to 74 percent.

House Democrats' support rose from 21 percent in the early months to 35 percent and 39 percent more recently.

Where they rank

McCain's 83 percent score for the year to date is next to last among Republican senators, ahead of only U.S. Sen. Susan Collins of Maine. Flake has supported Trump 92 percent of the time, but that puts him closer to the bottom than the middle in his party.

McSally's support ranks 85th in the House, which puts her in the top 20 percent of lawmakers.

By contrast, Biggs has the lowest Trump support among Arizona's House Republicans at 85 percent. That ranks 229th in the House, 10 spots ahead of the highest-ranked Democrat.

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