When it comes to public support of the health care reform law, the passage of time and favorable developments can make a big difference.

For all of 2014, the percentage of the population that had an unfavorable view of the Affordable Care Act exceeded those with a favorable view, sometimes by a fairly substantial margin, according to regular surveys by the Kaiser Family Foundation.

For example, in July 2014, 53% of adults surveyed by Kaiser said they had an unfavorable opinion of the law, while just 37% viewed the law favorably, and 11% didn't know.

But last month, for the first time since late 2012, the percentage of those with a favorable view of the law was higher, if only barely — 43% to 42% — than those with an unfavorable opinion, with 11% saying they didn't know, according to a Kaiser survey released Monday.

Certainly, a big factor in changing public views of the reform law is the spate of recent positive related developments. For example, last year, one of the dominant reform law-related stories — especially early in the year — were the problems individuals faced trying to enroll in health care plans offered in the public exchanges.

Another negative came later in the year, when the Obama administration, which had been boasting — despite technology-related problems — of how many people enrolled in exchange plan, scaled back enrollment figures.

In May 2014, for example, the administration said 8 million people had signed up for exchange coverage. But in November, regulators put the enrollment figure at 6.7 million, with much of the decline due to enrollees not paying premiums. In addition, administration officials acknowledged that about 400,000 people with stand-alone dental plans were incorrectly counted as having secured health coverage through the exchanges.

But this year, the news has been much more positive. About 11.7 million people signed up for plans offered in the public exchanges during the 2015 open enrollment season, with few reports about individuals having problems enrolling.

In addition, while Republican lawmakers in Congress last year made several efforts to repeal the health care reform law, GOP lawmakers most recently have been focusing on continuing — at least for a couple of years — federal premium subsidies for those obtaining coverage in federal exchanges in the event the Supreme Court strikes down the subsidies.

For example, legislation introduced by Sen. Ron Johnson, R-Wis., and backed by such Republican heavyweights as Senate Majority Leader Mitch McConnell, R-Ky., would continue those subsidies through August 2017 in the event the subsidies are stuck down by the high court.