California’s health insurance exchange estimates that its Obamacare premiums may rise 8 percent on average next year, which would end two consecutive years of more modest 4 percent increases.

The projected rate increase in California, included in the exchange’s proposed annual budget, comes amid growing nationwide concern about insurers seeking double-digit premium hikes in the health law’s  insurance marketplaces.

Any increases in California, a closely watched state in the health law rollout, are sure to draw intense scrutiny during a presidential election. Republicans are quick to seize on rate hikes as further proof that President Barack Obama’s signature law isn’t doing enough to hold down health care costs for the average consumer.

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